Autoimmune diseases are chronic debilitating conditions that collectively affect 5 to 8 % of the US population. The high prevalence of autoimmune diseases and the recognition that individuals who develop organ-specific autoimmune conditions have a high likelihood of developing additional autoimmune disorder(s) calls for the development of new technologies that can measure multiple immune reactivities simultaneously in a small sample volume. Detection of these diseases before onset or at early stages can help in making effective treatment decisions. Although multiplexing of up to 13 relevant assays for systemic autoimmune diseases has been achieved, broader panels have not been developed to assess the range of organ-specific autoimmune diseases such as Type 1 Diabetes and Celiac disease. Furthermore, no multiplexed assay panels exist that use a bridging immunoassay format, which provides higher assay specificity as compared to classical serological assay formats. The goal of the proposed program is to develop a novel, highly sensitive, and specific solution-based multiplexed bridging immunoassay panel that can simultaneously detect patient autoantibodies for 25 different autoimmune reactivities relevant to at least 12 major organ-specific autoimmune diseases. The multiplexed autoantibody detection panel will use sensitive Meso Scale Diagnostics, LLC. (MSD) MULTI-ARRAY technology. Our collaborators at the University of Florida, Dr. W.E. Winter and D. Pittmann, will provide their extensive expertise in clinical laboratory assessment of autoimmune diseases related to obesity, diabetes and the metabolic syndrome, and will provide high quality case and control samples for use in panel development, testing, and validation.